Campground charging checklist? What do I need?

[potato]

I thought that's what I said... the charger in the car / truck will not ask for more than 12 amps on a 120V line. The EVSE is just a "spigot".

True. I thought you kind of implied it was a necessary safety feature though. In my opinion it's a "misfeature". There are common situations where 120V at >15 amps is available safely - e.g. the campground TT-30 that sparked this discussion, and plenty of smaller generators. It's a bad assumption/design on Ford's part to not allow those to be used. In my opinion. Maybe there's some technical reason, but it's still a puzzling and annoying omission when lots of other EVs are not similarly crippled.

Sponsored

 

[21st Century Truck]

True. I thought you kind of implied it was a necessary safety feature though. In my opinion it's a "misfeature". There are common situations where 120V at >15 amps is available safely - e.g. the campground TT-30 that sparked this discussion, and plenty of smaller generators. It's a bad assumption/design on Ford's part to not allow those to be used. In my opinion. Maybe there's some technical reason, but it's still a puzzling and annoying omission when lots of other EVs are not similarly crippled.

AFAIK this 120V limitation is / was an agreed-on EV manufacturers' standard.

I can't cite a source... just that is how it always was presented in my past 13 years of using EVSEs from car manufacturers and aftermarket sellers.

Yes of course I wish that the TT-30 receptacle with its potential of 30 amps at 120V were fully usable by portable EVSEs... there are plenty of such very functional older receptacles available across National Forest and related campgrounds I've used across our four plug-in hybrid and EV cars since 2011.

At the same time, I also understand (again, afaik) why EVSE / EV manufacturers had agreed early on to limit 120V draws in their vehicle chargers to 12 amps, as at 120V this is by far the most often seen receptacle and circuit.

 

[Firn]

AFAIK this 120V limitation is / was an agreed-on EV manufacturers' standard.

I can't cite a source... just that is how it always was presented in my past 13 years of using EVSEs from car manufacturers and aftermarket sellers.

Yes of course I wish that the TT-30 receptacle with its potential of 30 amps at 120V were fully usable by portable EVSEs... there are plenty of such very functional older receptacles available across National Forest and related campgrounds I've used across our four plug-in hybrid and EV cars since 2011.

At the same time, I also understand (again, afaik) why EVSE / EV manufacturers had agreed early on to limit 120V draws in their vehicle chargers to 12 amps, as at 120V this is by far the most often seen receptacle and circuit.

By that logic 240v should be limited to 24a. The most common receptacle is the 14-30, p or r. So then regardless of what the evse says, power should be limited.

Sorry, I know you didn't make that decision. But if that is the logic used then by design the manufactures are ignoring the EVSE, which is the entire purpose the evse exists. It's illogical

Ironically Tesla ignores that and changes the rate of their mobile charger based upon the plug used.

 

[21st Century Truck]

By that logic 240v should be limited to 24a. The most common receptacle is the 14-30, p or r. So then regardless of what the evse says, power should be limited.

Sorry, I know you didn't make that decision. But if that is the logic used then by design the manufactures are ignoring the EVSE, which is the entire purpose the evse exists. It's illogical

Ironically Tesla ignores that and changes the rate of their mobile charger based upon the plug used.

Beyond my pay grade, and all that.

I'm certain there are EV consortium associations like all the other professional associations in existence in the USA... and based on how I understand fire protection associations, house building associations, medical associations and all their similar ilk, they get together in their professional conclaves and make (and often adjust) their association decisions, in our case the EVSE and EV power supply agreed-on standards that result in the equipment we live with. A friend had been a regular attendee at the annual home building inspectors' professional association, and the stories he told after their conclaves were both instructive and amusing.

I seem to dimly remember that the Society of Automotive Engineers (SAE) also evolved this way to eventually set define the standards for all the bolts and nuts we now use as "SAE" without even a thought.

In my humble opinion, as cantankerous as this naturally evolved North American professional self-evolved standard-setting system can be, it is far more responsive and flexible than, say, the ECE government committee standards the EU sets over across the Big Pond to our East.

 

[SpaceEVDriver]

AFAIK this 120V limitation is / was an agreed-on EV manufacturers' standard.

I can't cite a source... just that is how it always was presented in my past 13 years of using EVSEs from car manufacturers and aftermarket sellers.

Yes of course I wish that the TT-30 receptacle with its potential of 30 amps at 120V were fully usable by portable EVSEs... there are plenty of such very functional older receptacles available across National Forest and related campgrounds I've used across our four plug-in hybrid and EV cars since 2011.

At the same time, I also understand (again, afaik) why EVSE / EV manufacturers had agreed early on to limit 120V draws in their vehicle chargers to 12 amps, as at 120V this is by far the most often seen receptacle and circuit.

The J1772 standard allows for 16 Amps with 120 volts on a 20A circuit, but the issue is that it's impossible to *know* you're on a 20A receptacle without requiring a NEMA 5-20 plug be built into the EVSE. Requiring a 5-20P limits accessibility to the point of being almost useless, so most EVSEs are going to stick to a 5-15P and limit current to 12A.

 

[Firn]

The J1772 standard allows for 16 Amps with 120 volts on a 20A circuit, but the issue is that it's impossible to *know* you're on a 20A receptacle without requiring a NEMA 5-20 plug be built into the EVSE. Requiring a 5-20P limits accessibility to the point of being almost useless, so most EVSEs are going to stick to a 5-15P and limit current to 12A.

But that's aside the point. Multiple EVSEs use exchangable plug ends to determine how much current can be allowed. Tesla being the big one, but webasto, who makes our evse, also does the same, you can go to the Cadillac site and buy a TT-30 that works in the Caddy webasto unit (if even fits out mobile charger).

And regardless, the truck ignores the EVSE and says that if it's 120v it will NOT pull more than 12a.

 

[21st Century Truck]

But that's aside the point. Multiple EVSEs use exchangable plug ends to determine how much current can be allowed. Tesla being the big one, but webasto, who makes our evse, also does the same, you can go to the Cadillac site and buy a TT-30 that works in the Caddy webasto unit (if even fits out mobile charger).

And regardless, the truck ignores the EVSE and says that if it's 120v it will NOT pull more than 12a.

Yes... because it's the charger inside the truck that sets the demand (that tells the EVSE, whether portable one or a permanent one, how much to supply). If the charger senses a 120V connection, it'll set the demand at 12 amps.

Back when I ordered my 2012 plug-in Prius and ordered the associated Leviton 16 amp permanent EVSE box, the Toyota literature and the Toyota dealership EV lady were meticulous in explaining all this, then very new, stuff. About how the charger inside the car communicated to the EVSE thru the two small comms plugs about what the car's charger wanted, given the conditions it understood (my language here, 13 years later). And about how the EVSE, because of the new just-set EV association charging protocol standards, could / would only supply what the car's charger asked for. Which is why the Leviton 16-amp EVSE (at 240V) would only supply 12 amps because the Prius' internal charger only demanded 12 amps at 240V.

That same Leviton permanent EVSE began to supply 16 amps at 240V automatically when I sold the Prius and bought a 2015 Ford Fusion Energi... its car charger could and did demand more amps, and the old EVSE gave it all it could haha.

 

[Firn]

Yes... because it's the charger inside the truck that sets the demand (that tells the EVSE, whether portable one or a permanent one, how much to supply). If the charger senses a 120V connection, it'll set the demand at 12 amps.

No, that's not how that works and completely misses the entire point.

The EVSE sets the supply. It's entire job is simply to tell the truck how much it CAN demand. The EVSE does not "supply" anything, it isn't an active device in charging, all it does is let electricity through and tells the vehicle what it CAN use.
Sure, the truck CAN use less than available, which is the whole point of this discussion and why it would purposely charge at less than half the speed it could be charging at.

There is no reason for it to work different at 120v than it does at 240v

 

[21st Century Truck]

The EVSE sets the supply.

Yes of course the EVSE is there to set the supply. I note here that it's the car's charger which sets the demand for that particular EV car. Demand (what X is asking for) and supply (what Y can provide) are related yet not the same.

...and I wish everyone a Good Night!

 

[Firn]

Yes of course the EVSE is there to set the supply. I note here that it's the car's charger which sets the demand for that particular EV car. Demand (what X is asking for) and supply (what Y can provide) are related yet not the same.

...and I wish everyone a Good Night!

So again, obviously the truck can choose to use less than can be supplied. That is the entire point of the discussion.

Back to the point that was mentioned. He was speaking of 5-20 specifically. Which is aside the point of the truck using 12a on EVERY plug. Of course you cannot ask for more than 16a on 5-20, asking for more would violate the 80% rule of the NEC. But that in no way means you cannot use 24a on a TT-30, which is NOT a 5-20.

And again, as to that point, Tesla, Cadillac, and Webasto DO set the mobile chargers to allow more than 12a, more than 16a, when equipped with a TT-30 connector. And obviously Tesla is using more than 12a, and I'm assuming Caddy is too.

And yet here we are where Ford only draws 12a when it KNOWS it can use more.

And also again, the EVSE does not "supply" electricity. You are equivucating. It is a switch, not an active component. It is not "pushing" electricity to the vehicle, not in the way a DCFC does. It tells the vehicle WHAT it can demand, and monitors that. And again, the POINT of the discussion is that the truck is demanding far far less than it CAN.

 

[Newton]

Although the Webasto Go has a NMEA 14-50 plug, it is only a 32A charger. It does not limit amperage based on the plug, it limits it based on the voltage. It is either 15A or 32A, nothing else.

I agree that It is pretty frustrating that a TT-30 does not work as a 30A EVSE, that has caught me out even with a charger that allows me to set the amperage. There isn’t a good solution unless you want to involve some sort of transformer. Realize, though that a 30A circuit will be derated by 20% at 120V, so at best you are getting 2.8kW rather than the 1.0kW that I get when I plug into a 120V circuit. Yes, it is more than twice as fast but it wouldn’t be a fantastic improvement to get 56 miles overnight rather than 20.

EVSEs that allow you to set the curent limit and potentially draw more current than the circuit allows are a bit of a minefield for liability, the consequences of a fire are not trivial even without lithium batteries involved. I think that the Grizzl*E looks for voltage drop which is better than nothing, I guess, but I wish that somebody had an EVSE that would detect the converter plug being used and set the amperage accordingly.

Sponsored